Yarrow was a character appearing in the Locked Room series. It was a Cosmog who later evolved into a Lunala and who can change into a female yarrow plant. It debuted in The Room of Reverse Portal as the said flower form.


Yarrow first appeared when it fell out of nowhere in the Reverse Portal room, as a flower. It was mistaken as female, even it itself had forgotten this until the Blue Luma corrected this. However, the other Lumas still considered it as female in the flower form. Yarrow stayed in its Cosmog form, to be used to it, and not pretend to be a flower.

Yarrow made an essential role in The Room of Super Mario Galaxy. It was interactable when it evolved into Cosmoem, but when it evolved into a Lunala by the Cosmic Flute and the Moon Leaf, it knew the weakness of the enemies in Melty Molten Galaxy. In the Galaxy Reactor, it used Moongeist Beam at the strong barrier created by Immortelle, making access to it. However, it had to sacrifice itself with the Lumas as the said villain made it stronger.

Yarrow was mentioned multiple times by Richard Melon in Mass Attack, stating that he wanted it to come back in the future.


Yarrow was an energetic character and pretended to be cute. It wanted to be the center of attention, but it's not working out. It didn't know a lot outside space, since it came there and lived there. It wanted to learn a lot in the rooms, travelling with others.


Cosmog Evolutionary line

Yarrow didn't reveal this until a point in a room. It didn't want to be a Cosmog on the grounds, so it requested to the Blue Luma to be a flower. It stayed as the normal form, evolving throughout in the Room of Super Mario Galaxy. As Cosmoem, it never got to interact and didn't last a long time as a Lunala.

Flower Form

Yarrow used the flower form quite well. It was referred as a female, but really, it was still gender-neutral. It dod not want to fight at first, but later on it got to attack at CRUNCH to make it be attacked. It wasn't used for long however.



  • Yarrow doesn't want to travel outside space until the portal to the Locked Rooms forced it to do so.
  • Yarrow likes perfume, but doesn't own one.
  • Shortly after Yarrow was made in the IaLR series, it went to a PvZ creation that was never continued until May 19, 2017. It was renamed to Yarrow Launcher, a pun of "Arrow Launcher". In addition, the IaLR Yarrow in flower form may be redesigned like the current design of the Yarrow Launcher plant (specifically recoloring, and having a slight edit).
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